EXPERIMENTAL ANALYSIS OF DEBONDING FAILURE OF STRENGTHENING PRESTRESSED RC BEAM WITH CFRP SHEETS

Though the performance of ordinary RC structures strengthened with CFRP sheet has been deeply studied， the research on the strengthened performance of prestressed concrete structures is seldom． Therefore，in order to study the influence of the bonding performance between CFRP sheets and the prestressed concrete structures on its structural behavior，the static tests of 3 high strength prestressed RC beam with different damage degree strengthened by CFRP sheets were carried out to study the influence of damage degree and prestressed degree on its bonding performance． Test result shows that CFRP sheets are all debonded before the specimen damaged，when the test specimen is damaged，CFRP sheets completely debonded，tensile failure or the concrete crushed in the compressive zone． The CFRP sheet-load curve and deflection-load curve of the test specimens show that the debonding load of the specimens is inversely proportional to its damage degree，but is proportional to the prestressed degree．